Self-calculating scale.



W. F. THOM`PSON. SELF GALGULATING. SCALE! APPLICATION rI-Ln'n Arn.5191a.

W. THQM PSOM.

@AML-m.

Patented .May 5, 1.914 l UNITED STATES PATENT OFFTCE,

N31LLIM'. F. CDI-IOMPSON, 0F SPRINGFIELD, MISSOURI, ASSGNOR CE ONE-HALF TO XVILLIAM C. LOHMEYER, OF SPRINGFIELD, MSSOURI.

SELF-CALCULATING SCALE,

Specification of Letters Patent* A Patented May 5, 1914.

' Appiication med april 5, 1913. Serin No. 759,124.

To all whom 'it may concern.

` son, a citizen of the United States, residing at Springfield, in the county of Greene and State of Missouri, have invented certain new and useful Improvements in Self-Calculating Scales, of which the following is a. specification, reference being. had to the accompanying drawings. y

This invention comprehends certain new and useful improvements in calculating in struments and has for its primary object to provide a. device of this character which will be of extremely simple construction and highly eiicient in use.

Another object is to provide a scale of this character which will be especially1 adapted for use by machinists in setting valves on locomotives or other steam engines.

Another object is to provide an instruinentof this character by means of which the workman may readily determine the change necessary to.an eccentric blade of a valve to properly adjust the valve rod.

Another object is to provide a device of this character by means of which the Workman may readily determine the change necessary to the oif-setcf the eccentric block when' adjusting the valves of steam engines a nd the like.

A further object is to provide a calculatingscale of this character by means of which the degree of changes necessary may be read ily calculated by simply moving the pivoted indicator beam and securing the same in ad- .justed position, said indicator beam 'having a beveled edge crossing graduated lines upon the face of the scale and the beam also being provided with an indicating point engaged with a graduated curved or arcuate line at one end of the scale or plate.

A further object is to provide a calculating scale of this type which will be of eX- tremely simple construction and opera-tion and highly efficient and accurate in use.A

Vith the above and other objects in View, this invention consists in the novel features of construction, combination and arrangement of parts to be hereinafter more fully described, claimed and illustrated in the ac compa-nying drawings, in which- Figure 1, is a plan View of my improved calculating instrument. Fig= Q, is an end view, looking at the lower end 'of the tool. Fig. 3, isa similar view looking at the upper end of the tool. Fig. a, is an enlarged deltail view to show more correctly the marliings upon the plate, the central portion of the tool being broken awzjand the ends brought closer together. Fig. 5, is a detail view of the beam pivoting member removed. Fig. (3, is a detail view of the thumb-screw removed.

Referring more specifically to the drawings in which similar reference characters designate corresponding parts throughout the several views, l designates the plate which is of rectangular form in generaloutline and preferably formed of a thin durable material and may be of any preferred dimensions but is preferably about two inches Awide and fteen inches long, the purpose of which will presently appear. The plate is provided upon one face with a longitudinal line 2 about onefonrth of an inch inwardly vof the left edge of said plate and transverse lines 3 are aiso provided one-half an inch apart, the lines indicating the inches extending clearly across the plate and the lines indicating the half inches extending only half the' distance between the longitudinal line and the opposite edge of the plate. The

transverse lines 3 are graduated to indicate one thirty second inches and one sixty fourth inches, as shown at e. The plate i is graduated along its left edge to indicate oneeigh'th inches between the inch indicating lines 3, as shown at 5 While suitable marl;- ings (i are provided along the opposite edge of the plate to indicate one-siateenth inches.

The indicator beam 7 is pivoted at its vlower end to the front or graduated face of the plate 1, by means of the pivot pin S which extends through the lower end of the lbeam and has a slightly reduced threaded portion 9 threaded through. the plate l., adjacent the lower end of said plate and slightly inwardly of the longitudinal line The indicator beam 7 is formed of any suitable thin material and has a beveled edge l0 and when the indicator beam is in one position, the beveled edge l0 thereof is engaged against the longitudinal line 2 and the of theV indicator beam is therefore parallel with the adjacent or left edge of the plate 1.

Adjacent the opposite or upper end of the plate l and preferably above the transverse line 3 indicating the fourteenth .inch of the scale, I have provided a curved or arcuate slot 1l which extends across the plato and has one endterminating adjacent the longitudinal line 2 While the opposite i end is located adjacent the opposite edge ci? the plate. A. curved or arcuate line`12 is pr vided above the slot 11 and spaced from the same, said line extendin in curvature of the slot 11v and having t e graduation marks'l positioned along said line to indicate the degrees ofv circle, the purpose of lo 'which'will presently, appear. The thumbscrew lt'extends through the slot 11 from the rear face of the plate and has its threaded port-ion 15 engaged in the upper end of the indicator beam .7 extending across the slet 11. The thumb-screw 14 serves as means to move the indicator beam and secure the same in adjusted position With the extended indicating, point 16 of the beam 7 pointing to the proper graduation mark 13, by tightening the thumb-screw 14 and thereby binding the upper or fnee end of the indicator beam'against the front face of the plate 1.' It. will be understood that the-indicating point 16 is formed by extending the beveled or front edge 10 of the'indicaytor beam 6 beyond the remaining portion of the upper or free end of said beam.

In use, when employing the instrument or scale to ascertain the change necessary to the eccentric blade of a locomotive or other valve and thevchange shown on valve rod is seven-thirty-seconds inch and assuming that the top rocker arm is l2 inches long and the bottom arm ten and ahalf inches long, I,

ing the radius of the valve travel is two and one-half inches and the radius of the jourbeam over three-thirty-seconds on the 'two and a hairD inch line on the scale. The proper ofi-set for the eccentric key is then indicated by the four inch line. It will be seen that by employing this scale,vmuch time and labor is saved. It will be understood that this calculating scale may be employed in many other and similar cases and will be accurate and eiicient in use.

YWhile I have shown the preferred embodiment of my invention, it will be understood that minor changes in the details oi construction may be made Within the scope of the appended claim, Without departing from the spirit of my invention.

Having thus described my invention, what I claim is A device of the class described comprisinge rectangular plate provided with an o'peningadjacent one corner and a transversely extending arcuate slot adjacent the opposite end of said plate, in combination with an indicator beam having one ace beveled and extended at one-end 'to form an indicator point, said plato having a scale upon one longitudinal edge and transverse scales extending across one face from the` scale upon said longitudinal edge, the transverse scales being spaced apart, a pivot member carried by .one end of the indicator beam and secured in said opening, and a combined guide and locking member carried by gthe opposite end of the beam andA engaged through saidslot of the plate for guiding the beam and securing the same in adjusted position upon the plate.

-In estimony whereof I hereunto affix my signature in the presence of two Witnesses. WILLIAM l?. THGMPSUN. Witnesses:

CHESTER T. Hnacoon, JESSE B. SMITH.

Copies of this patent may be obtained for tive cents each, by addressing the Commissioner of Patents.

' Washington, D. G. 

